#!/usr/bin/env python
# -*- coding: utf8 -*-
# $Id$

# rst2pdf.py
# ==========
# ::

"""
A front end to the Docutils Publisher, producing PDF.

Produces a latex file with the "latex" writer and converts
it to PDF with the "rubber" building system for LaTeX documents. 
"""

# ``rst2pdf.py`` is a PDF front-end for docutils that is compatible
# with the ``rst2*.py`` front ends of the docutils_ suite.
# It enables the generation of PDF documents from a reStructuredText source in
# one step.
# 
# It is implemented as a combination of docutils' ``rst2latex.py`` 
# by David Goodger and rubber_ by Emmanuel Beffara.
# 
# Copyright: © 2008 Günter Milde
#            Licensed under the `Apache License, Version 2.0`_
#            Provided WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND
# 
# Changelog
# ---------
# 
# =====  ==========  =======================================================
# 0.1    2008-05-20  first attempt
# =====  ==========  =======================================================
# 
# :: 

_version = 0.1


# Imports
# =======
# ::

#from pprint import pprint # for debugging
import os

# Docutils::

try:
    import locale
    locale.setlocale(locale.LC_ALL, '')
except:
    pass

from docutils.core import default_usage, default_description, Publisher

# Rubber (rubber is not installed in the PYTHONPATH)::

import sys
sys.path.append("/usr/share/rubber")

try:
    import rubber.cmdline
    import rubber.cmd_pipe
except ImportError:
    print "Cannot find the rubber modules, rubber not installed correctly."
    sys.exit(1)

# Generate the latex file
# =======================
# 
# We need to replace the <destination> by a intermediate latex file path.
# The most reliable way to get the value of <destination> is to 
# call the Publisher "by hand", and query its settings. 
# 
# Modeled on the publish_cmdline() function of docutils.core
# 
# Default values::

reader=None
reader_name='standalone'
parser=None
parser_name='restructuredtext'
writer=None
writer_name='pseudoxml'
settings=None
settings_spec=None
settings_overrides=None
config_section=None
enable_exit_status=1
argv=None
usage=default_usage
description=default_description

# Argument values given to publish_cmdline() in rst2latex.py::

description = ('Generates PDF documents from standalone reStructuredText '
               'sources using the "latex" Writer and the "rubber" '
               'building system for LaTeX documents.  ' + default_description)
writer_name = 'latex'

# Set up the publisher::

pub = Publisher(reader, parser, writer, settings=settings)
pub.set_components(reader_name, parser_name, writer_name)

# Parse the command line args 
# (Publisher.publish does this in a try statement)::

pub.process_command_line(argv, usage, description, settings_spec, 
                         config_section, **(settings_overrides or {}))
# pprint(pub.settings.__dict__)

# Get source and destination path::

source = pub.settings._source
destination = pub.settings._destination
# print source, destination

# Generate names for the temporary files and set ``destination`` to temporary
# latex file:
# 
# make_name() from rubber.cmd_pipe checks that no existing file is
# overwritten. If we are going to support rubbers ``--inplace`` and ``--into``
# options, the chdir() must occure before this point to have the check in the
# right directory. ::

tmppath = rubber.cmd_pipe.make_name()
texpath = tmppath + ".tex"
pdfpath = tmppath + ".pdf"

pub.settings._destination = texpath

# Now do the rst -> latex conversion::

pub.publish(argv, usage, description, settings_spec, settings_overrides, 
            config_section=config_section, enable_exit_status=enable_exit_status)


# Generating the PDF document with rubber
# =======================================
# 
# 
# rubber_ has no documentet API for programmatic use. We simualate a command
# line call and pass command line arguments (see man: rubber-pipe) in an array::

rubber_argv = ["--pdf",    # use pdflatex to produce PDF
               "--short",   # Display LaTeX’s error messages one error per line.
               texpath
              ]

# Get a TeX processing class instance and do the latex->pdf conversion::

tex_processor = rubber.cmdline.Main()
tex_processor(rubber_argv)

# Rename output to _destination or print to stdout::

if destination is None:
    pdffile = file(pdfpath)
    print  pdffile.read()
    pdffile.close()
else:
    os.rename(pdfpath, destination)

# Clean up (remove intermediate files)
# 
# ::

tex_processor(["--clean"] + rubber_argv)
os.remove(texpath)


# .. References
# 
# .. _docutils: http://docutils.sourceforge.net/
# .. _rubber: http://www.pps.jussieu.fr/~beffara/soft/rubber/
# .. _Apache License, Version 2.0: http://www.apache.org/licenses/LICENSE-2.0
#                                                                         
